Fix: sessiond: ust: deadlock with per-pid buffers
[lttng-tools.git] / src / bin / lttng-relayd / session.c
CommitLineData
2f8f53af
DG
1/*
2 * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
3 * David Goulet <dgoulet@efficios.com>
7591bab1 4 * 2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
2f8f53af
DG
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License, version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19
6c1c0768 20#define _LGPL_SOURCE
2a174661 21#include <common/common.h>
a620c891 22#include <common/utils.h>
1e791a74 23#include <common/compat/uuid.h>
7591bab1 24#include <urcu/rculist.h>
2a174661 25
d37856b8
JR
26#include <sys/stat.h>
27
2a174661 28#include "ctf-trace.h"
a620c891 29#include "lttng-relayd.h"
2f8f53af 30#include "session.h"
23c8ff50 31#include "sessiond-trace-chunks.h"
a620c891 32#include "stream.h"
a0409c33 33#include <common/defaults.h>
d37856b8 34#include "utils.h"
2a174661
DG
35
36/* Global session id used in the session creation. */
37static uint64_t last_relay_session_id;
7591bab1 38static pthread_mutex_t last_relay_session_id_lock = PTHREAD_MUTEX_INITIALIZER;
2a174661 39
ecd1a12f
MD
40static int init_session_output_path(struct relay_session *session)
41{
42 /*
43 * session_directory:
44 *
45 * if base_path is \0'
46 * hostname/session_name
47 * else
48 * hostname/base_path
49 */
50 char *session_directory = NULL;
51 int ret = 0;
52
53 if (session->output_path[0] != '\0') {
54 goto end;
55 }
56 /*
57 * If base path is set, it overrides the session name for the
58 * session relative base path. No timestamp is appended if the
59 * base path is overridden.
60 *
61 * If the session name already contains the creation time (e.g.
62 * auto-<timestamp>, don't append yet another timestamp after
63 * the session name in the generated path.
64 *
65 * Otherwise, generate the path with session_name-<timestamp>.
66 */
67 if (session->base_path[0] != '\0') {
68 ret = asprintf(&session_directory, "%s/%s", session->hostname,
69 session->base_path);
70 } else if (session->session_name_contains_creation_time) {
71 ret = asprintf(&session_directory, "%s/%s", session->hostname,
72 session->session_name);
73 } else {
74 char session_creation_datetime[16];
75 size_t strftime_ret;
76 struct tm *timeinfo;
77 time_t creation_time;
78
79 /*
80 * The 2.11+ protocol guarantees that a creation time
81 * is provided for a session. This would indicate a
82 * protocol error or an improper use of this util.
83 */
84 if (!session->creation_time.is_set) {
85 ERR("Creation time missing for session \"%s\" (protocol error)",
86 session->session_name);
87 ret = -1;
88 goto end;
89 }
90 creation_time = LTTNG_OPTIONAL_GET(session->creation_time);
91
92 timeinfo = localtime(&creation_time);
93 if (!timeinfo) {
94 ERR("Failed to get timeinfo while initializing session output directory handle");
95 ret = -1;
96 goto end;
97 }
98 strftime_ret = strftime(session_creation_datetime,
99 sizeof(session_creation_datetime),
100 "%Y%m%d-%H%M%S", timeinfo);
101 if (strftime_ret == 0) {
102 ERR("Failed to format session creation timestamp while initializing session output directory handle");
103 ret = -1;
104 goto end;
105 }
106 ret = asprintf(&session_directory, "%s/%s-%s",
107 session->hostname, session->session_name,
108 session_creation_datetime);
109 }
110 if (ret < 0) {
111 PERROR("Failed to format session directory name");
112 goto end;
113 }
114
115 if (strlen(session_directory) >= LTTNG_PATH_MAX) {
116 ERR("Session output directory exceeds maximal length");
117 ret = -1;
118 goto end;
119 }
120 strcpy(session->output_path, session_directory);
121 ret = 0;
122
123end:
124 free(session_directory);
125 return ret;
126}
127
1e791a74
JG
128static int session_set_anonymous_chunk(struct relay_session *session)
129{
130 int ret = 0;
131 struct lttng_trace_chunk *chunk = NULL;
132 enum lttng_trace_chunk_status status;
133 struct lttng_directory_handle output_directory;
134
d37856b8 135 ret = session_init_output_directory_handle(session, &output_directory);
1e791a74
JG
136 if (ret) {
137 goto end;
138 }
139
140 chunk = lttng_trace_chunk_create_anonymous();
141 if (!chunk) {
142 goto end;
143 }
144
145 status = lttng_trace_chunk_set_credentials_current_user(chunk);
146 if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
147 ret = -1;
148 goto end;
149 }
150
151 status = lttng_trace_chunk_set_as_owner(chunk, &output_directory);
152 if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
153 ret = -1;
154 goto end;
155 }
156 session->current_trace_chunk = chunk;
157 chunk = NULL;
158end:
159 lttng_trace_chunk_put(chunk);
160 lttng_directory_handle_fini(&output_directory);
161 return ret;
162}
163
2a174661
DG
164/*
165 * Create a new session by assigning a new session ID.
166 *
167 * Return allocated session or else NULL.
168 */
7591bab1 169struct relay_session *session_create(const char *session_name,
6fa5fe7c 170 const char *hostname, const char *base_path,
db1da059
JG
171 uint32_t live_timer,
172 bool snapshot,
173 const lttng_uuid sessiond_uuid,
174 const uint64_t *id_sessiond,
175 const uint64_t *current_chunk_id,
176 const time_t *creation_time,
177 uint32_t major,
46ef2188
MD
178 uint32_t minor,
179 bool session_name_contains_creation_time)
2a174661 180{
23c8ff50 181 int ret;
590f0324
JG
182 struct relay_session *session = NULL;
183
5c956ba3
JG
184 assert(session_name);
185 assert(hostname);
186 assert(base_path);
187
188 if (strstr(session_name, ".")) {
590f0324
JG
189 ERR("Illegal character in session name: \"%s\"",
190 session_name);
191 goto error;
192 }
5c956ba3 193 if (strstr(base_path, "../")) {
590f0324
JG
194 ERR("Invalid session base path walks up the path hierarchy: \"%s\"",
195 base_path);
196 goto error;
197 }
5c956ba3 198 if (strstr(hostname, ".")) {
590f0324
JG
199 ERR("Invalid character in hostname: \"%s\"",
200 hostname);
201 goto error;
202 }
2a174661
DG
203
204 session = zmalloc(sizeof(*session));
205 if (!session) {
1e791a74 206 PERROR("Failed to allocate session");
2a174661
DG
207 goto error;
208 }
bb5d54e7
MD
209 if (lttng_strncpy(session->session_name, session_name,
210 sizeof(session->session_name))) {
1e791a74 211 WARN("Session name exceeds maximal allowed length");
bb5d54e7
MD
212 goto error;
213 }
214 if (lttng_strncpy(session->hostname, hostname,
215 sizeof(session->hostname))) {
1e791a74 216 WARN("Hostname exceeds maximal allowed length");
bb5d54e7
MD
217 goto error;
218 }
6fa5fe7c
MD
219 if (lttng_strncpy(session->base_path, base_path,
220 sizeof(session->base_path))) {
221 WARN("Base path exceeds maximal allowed length");
222 goto error;
223 }
46ef2188
MD
224 if (creation_time) {
225 LTTNG_OPTIONAL_SET(&session->creation_time, *creation_time);
226 }
227 session->session_name_contains_creation_time =
228 session_name_contains_creation_time;
6fa5fe7c 229
2a174661
DG
230 session->ctf_traces_ht = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
231 if (!session->ctf_traces_ht) {
2a174661
DG
232 goto error;
233 }
234
7591bab1 235 pthread_mutex_lock(&last_relay_session_id_lock);
2a174661 236 session->id = ++last_relay_session_id;
7591bab1
MD
237 pthread_mutex_unlock(&last_relay_session_id_lock);
238
239 session->major = major;
240 session->minor = minor;
2a174661 241 lttng_ht_node_init_u64(&session->session_n, session->id);
7591bab1
MD
242 urcu_ref_init(&session->ref);
243 CDS_INIT_LIST_HEAD(&session->recv_list);
244 pthread_mutex_init(&session->lock, NULL);
7591bab1
MD
245 pthread_mutex_init(&session->recv_list_lock, NULL);
246
7591bab1
MD
247 session->live_timer = live_timer;
248 session->snapshot = snapshot;
23c8ff50
JG
249 lttng_uuid_copy(session->sessiond_uuid, sessiond_uuid);
250
1e791a74
JG
251 if (id_sessiond) {
252 LTTNG_OPTIONAL_SET(&session->id_sessiond, *id_sessiond);
253 }
254
d519f442
JR
255 if (major == 2 && minor >= 11) {
256 /* Only applies for 2.11+ peers using trace chunks. */
257 ret = init_session_output_path(session);
258 if (ret) {
259 goto error;
260 }
ecd1a12f 261 }
d519f442 262
23c8ff50
JG
263 ret = sessiond_trace_chunk_registry_session_created(
264 sessiond_trace_chunk_registry, sessiond_uuid);
265 if (ret) {
266 goto error;
267 }
7591bab1 268
1e791a74
JG
269 if (id_sessiond && current_chunk_id) {
270 session->current_trace_chunk =
271 sessiond_trace_chunk_registry_get_chunk(
272 sessiond_trace_chunk_registry,
273 session->sessiond_uuid,
274 session->id_sessiond.value,
275 *current_chunk_id);
276 if (!session->current_trace_chunk) {
277 char uuid_str[UUID_STR_LEN];
278
279 lttng_uuid_to_str(sessiond_uuid, uuid_str);
280 ERR("Could not find trace chunk: sessiond = {%s}, sessiond session id = %" PRIu64 ", trace chunk id = %" PRIu64,
281 uuid_str, *id_sessiond,
282 *current_chunk_id);
283 }
284 } else if (!id_sessiond) {
285 /*
286 * Pre-2.11 peers will not announce trace chunks. An
287 * anonymous trace chunk which will remain set for the
288 * duration of the session is created.
289 */
290 ret = session_set_anonymous_chunk(session);
291 if (ret) {
292 goto error;
293 }
294 }
295
7591bab1 296 lttng_ht_add_unique_u64(sessions_ht, &session->session_n);
bb5d54e7 297 return session;
2a174661
DG
298
299error:
1e791a74 300 session_put(session);
bb5d54e7 301 return NULL;
2a174661 302}
2f8f53af 303
7591bab1
MD
304/* Should be called with RCU read-side lock held. */
305bool session_get(struct relay_session *session)
306{
ce4d4083 307 return urcu_ref_get_unless_zero(&session->ref);
7591bab1
MD
308}
309
2f8f53af 310/*
7591bab1
MD
311 * Lookup a session within the session hash table using the session id
312 * as key. A session reference is taken when a session is returned.
313 * session_put() must be called on that session.
2f8f53af
DG
314 *
315 * Return session or NULL if not found.
316 */
7591bab1 317struct relay_session *session_get_by_id(uint64_t id)
2f8f53af
DG
318{
319 struct relay_session *session = NULL;
2a174661 320 struct lttng_ht_node_u64 *node;
2f8f53af
DG
321 struct lttng_ht_iter iter;
322
7591bab1
MD
323 rcu_read_lock();
324 lttng_ht_lookup(sessions_ht, &id, &iter);
2a174661 325 node = lttng_ht_iter_get_node_u64(&iter);
2f8f53af 326 if (!node) {
2a174661 327 DBG("Session find by ID %" PRIu64 " id NOT found", id);
2f8f53af
DG
328 goto end;
329 }
330 session = caa_container_of(node, struct relay_session, session_n);
2a174661 331 DBG("Session find by ID %" PRIu64 " id found", id);
7591bab1
MD
332 if (!session_get(session)) {
333 session = NULL;
334 }
2f8f53af 335end:
7591bab1 336 rcu_read_unlock();
2f8f53af
DG
337 return session;
338}
2a174661 339
7591bab1
MD
340static void rcu_destroy_session(struct rcu_head *rcu_head)
341{
342 struct relay_session *session =
343 caa_container_of(rcu_head, struct relay_session,
344 rcu_node);
49e614cb
MD
345 /*
346 * Since each trace has a reference on the session, it means
347 * that if we are at the point where we teardown the session, no
348 * trace belonging to that session exist at this point.
349 * Calling lttng_ht_destroy in call_rcu worker thread so we
350 * don't hold the RCU read-side lock while calling it.
351 */
352 lttng_ht_destroy(session->ctf_traces_ht);
7591bab1
MD
353 free(session);
354}
355
2a174661
DG
356/*
357 * Delete session from the given hash table.
358 *
359 * Return lttng ht del error code being 0 on success and 1 on failure.
360 */
7591bab1 361static int session_delete(struct relay_session *session)
2a174661
DG
362{
363 struct lttng_ht_iter iter;
364
2a174661 365 iter.iter.node = &session->session_n.node;
7591bab1 366 return lttng_ht_del(sessions_ht, &iter);
2a174661
DG
367}
368
7591bab1
MD
369
370static void destroy_session(struct relay_session *session)
371{
372 int ret;
373
374 ret = session_delete(session);
375 assert(!ret);
639ddf68 376 lttng_trace_chunk_put(session->current_trace_chunk);
c35f9726 377 session->current_trace_chunk = NULL;
62bad3bf
JG
378 lttng_trace_chunk_put(session->pending_closure_trace_chunk);
379 session->pending_closure_trace_chunk = NULL;
23c8ff50
JG
380 ret = sessiond_trace_chunk_registry_session_destroyed(
381 sessiond_trace_chunk_registry, session->sessiond_uuid);
382 assert(!ret);
7591bab1
MD
383 call_rcu(&session->rcu_node, rcu_destroy_session);
384}
385
386void session_release(struct urcu_ref *ref)
2a174661 387{
7591bab1
MD
388 struct relay_session *session =
389 caa_container_of(ref, struct relay_session, ref);
2a174661 390
7591bab1
MD
391 destroy_session(session);
392}
2a174661 393
7591bab1
MD
394void session_put(struct relay_session *session)
395{
874ec45e
JG
396 if (!session) {
397 return;
398 }
7591bab1 399 rcu_read_lock();
7591bab1 400 urcu_ref_put(&session->ref, session_release);
7591bab1 401 rcu_read_unlock();
2a174661
DG
402}
403
7591bab1 404int session_close(struct relay_session *session)
2a174661
DG
405{
406 int ret = 0;
7591bab1
MD
407 struct ctf_trace *trace;
408 struct lttng_ht_iter iter;
409 struct relay_stream *stream;
410
411 pthread_mutex_lock(&session->lock);
412 DBG("closing session %" PRIu64 ": is conn already closed %d",
413 session->id, session->connection_closed);
7591bab1 414 session->connection_closed = true;
7591bab1 415 pthread_mutex_unlock(&session->lock);
2a174661 416
7591bab1
MD
417 rcu_read_lock();
418 cds_lfht_for_each_entry(session->ctf_traces_ht->ht,
419 &iter.iter, trace, node.node) {
420 ret = ctf_trace_close(trace);
421 if (ret) {
422 goto rcu_unlock;
2a174661
DG
423 }
424 }
7591bab1
MD
425 cds_list_for_each_entry_rcu(stream, &session->recv_list,
426 recv_node) {
bda7c7b9
JG
427 /* Close streams which have not been published yet. */
428 try_stream_close(stream);
7591bab1
MD
429 }
430rcu_unlock:
431 rcu_read_unlock();
432 if (ret) {
433 return ret;
434 }
435 /* Put self-reference from create. */
436 session_put(session);
437 return ret;
2a174661
DG
438}
439
98ba050e
JR
440int session_abort(struct relay_session *session)
441{
442 int ret = 0;
443
444 if (!session) {
445 return 0;
446 }
447
448 pthread_mutex_lock(&session->lock);
449 DBG("aborting session %" PRIu64, session->id);
98ba050e 450 session->aborted = true;
98ba050e
JR
451 pthread_mutex_unlock(&session->lock);
452 return ret;
453}
454
7591bab1 455void print_sessions(void)
2a174661 456{
2a174661 457 struct lttng_ht_iter iter;
7591bab1 458 struct relay_session *session;
2a174661 459
ce3f3ba3
JG
460 if (!sessions_ht) {
461 return;
462 }
463
2a174661 464 rcu_read_lock();
7591bab1
MD
465 cds_lfht_for_each_entry(sessions_ht->ht, &iter.iter, session,
466 session_n.node) {
467 if (!session_get(session)) {
468 continue;
469 }
470 DBG("session %p refcount %ld session %" PRIu64,
471 session,
472 session->ref.refcount,
473 session->id);
474 session_put(session);
2a174661 475 }
2a174661 476 rcu_read_unlock();
2a174661 477}
d37856b8
JR
478
479int session_init_output_directory_handle(struct relay_session *session,
480 struct lttng_directory_handle *handle)
481{
482 int ret;
483 /*
484 * relayd_output_path/session_directory
485 * e.g. /home/user/lttng-traces/hostname/session_name
486 */
487 char *full_session_path = NULL;
488
489 pthread_mutex_lock(&session->lock);
490 full_session_path = create_output_path(session->output_path);
491 if (!full_session_path) {
492 ret = -1;
493 goto end;
494 }
495
496 ret = utils_mkdir_recursive(
497 full_session_path, S_IRWXU | S_IRWXG, -1, -1);
498 if (ret) {
499 ERR("Failed to create session output path \"%s\"",
500 full_session_path);
501 goto end;
502 }
503
504 ret = lttng_directory_handle_init(handle, full_session_path);
505 if (ret) {
506 goto end;
507 }
508end:
509 pthread_mutex_unlock(&session->lock);
510 free(full_session_path);
511 return ret;
512}
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